I have a 2003 6.0 with roughly 140,000 on it. I have owned it for less than six months, since purchasing it I have pretty much gotten to be intamately involved. Let me clear that up! When I got the truck home I figgured the mileage at somewhere around 17mpg. Thats when I started my research on this motor to get better aquainted with it. I read about a egr delete, head stud swap, oil cooler failure, Yata yata yata!!! Truth is if you research any motor you will come up information overload, which will steer you away from all diesels period and you will end up driving a prius. Long story short, My feelings are mixed on this truck (which btw I bought with the money I got from selling my 94 7.3). I went ahead and did an egr delete, cat delete,cold air intake and oil cooler replacement right away as preventitive maintenance, and hopefully increasing mpgs. When complete could not get truck to start at all. Thats when I learned about the High Pressure oil system on these trucks. If your not aware of this let me give you the low down. Basically the oil pressure is what opens and closes the injectors, which means oil changes need to be done on a regular basis ( about every 3000 miles). When replacing the oil cooler, although being extremely careful, I got a slight amount of debris in oil valley, which in turn had damaged the ipr (injection pressure regulator) and would not allow the truck to start. Btw ipr is about 300 bucks. After replacing IPR, by hypothesis, truck ran well and mpgs were increased to around 19-21 mpg. The truck now ran like a dream except one thing. When at lower altitudes for some reason when shut off hot, truck re-started hard. Trottle response was good, turbo spool was amazing, and mpgs stayed consistant, just hard starts. Last monday my wife was about to turn in the drive way when the truck just died. It continues to sit there now as I wait on parts. I suspect it to be a cam position sensor although rare on these 6.0s, but am also replacing IPR, ICP, and debating putting a new High Pressure Oil pump in, as I removed turbo to get to IPR. Not trying to scare you away, as this thing is nice to drive when It runs good, just more less wanted to give you a heads up before your purchase. There is a wealth of information on this motor due to its reputation as being junk, But most problems are created from folks like me who dont have scanners, and just guess what the problem is. So far my diagnostics have been pretty good, but like I said neglect to clean valley pan thoroughly when doing oil cooler is what caused my IPR to fail, and possably my HPOP as well, we'll see!! Get the thing checked out on a scanner from a reputable mechanic that knows these trucks, and keep up on the maintenance.
Hope this helps
God Bless
So I am on the search again, honestly I would rather go to a 250 , my dad has an 03 with 4 wheel drive and that is more what I want.
